What Is A Subwoofer?

In this article, we'll focus on subwoofers and the enclosures (or "boxes") they may be housed in. But first, we'll clarify the differences between a subwoofer and a woofer. Both these terms are often mixed up, creating confusion about functions these components serve.

Woofers are an integral part of a 3-way speaker setup. (For more information on general terms used for car audio systems, see our related article Audio Speaker Basics on the subject.) Woofers are often contained in one speaker housing along with two other audio drivers known as a tweeter (creates high-frequency sounds) and a "mid-range" (creates sounds in the middle of the sound spectrum). Woofers reproduce lower frequency bass sounds and, depending on design, they may cover some of the middle range frequency notes as well.

Subwoofers are extra, add-on equipment not usually found in car audio systems. They're all about the bass, and their whole point of existence is to assist woofer drivers in accentuating the lowest frequency sounds. Technically, a subwoofer is a driver rather than a full-range speaker - but it's still common to see subwoofers referred to as speakers.

Subwoofers can be mounted anywhere in the vehicle, and we've got all shapes and sizes to suit your demands in our Subwoofers & Boxes section. There, you'll find individual replacement subwoofers, complete box assemblies with subwoofers installed, pipe-shaped bass tubes, and a variety of empty housings if you prefer to build your own. Many of the subwoofer box assemblies and bass tubes come with their own built-in amplifiers - those so equipped will state so on the product page.

Power Capacity Of Subwoofers And Why It Matters

When looking at subwoofers sold individually or inside boxed enclosures, it's important to know the measurements of a subwoofer's ability to perform and what each of those measurements signifies. You'll often see peak watts referenced - this is the most power a speaker can handle for a short burst (typically the loudest point in a song, for example). This is not so important, because speakers will not be played at peak watts 99% of the time.

RMS (Root Mean Square) watts is a number worth paying attention to because it reflects the sustained power capability of the subwoofer - or, the wattage a subwoofer can handle for long stretches of time without overheating, blowing out, or creating distortion. Subwoofers perform their best when power levels are reaching the high end of their RMS watt range. So if you'll be using a factory or aftermarket radio without an amplifier, lower RMS-rated subwoofers are actually the ones that sound clearest and best at standard volume levels. If you'll be adding an external amplifier to generate more power for louder volumes without distortion, subwoofers with higher RMS ratings will sound best.

The decibel level rating (also known as "SPL" / sound pressure level) of a subwoofer is also important because this is the line above which sound becomes distorted. Decibel levels may also be referred to as "sensitivity level". A common misconception is that bigger subwoofers always need more power, but the fact is they do not. An efficiency rating indicator helps here, because it specifies how much decibel output will be yielded from a given amount of power. A number rating in the 80s is good, and anything above 90 is considered the best.

Unlike higher-frequency tweeters and mid-ranges, the tone, pitch, or sound of a subwoofer is not really affected by the cone materials. Metal may result in longer longevity over paper materials, but they'll all sound good since the sole job of a subwoofer is a basic one - to push air. You may also see the phrase "pre-loaded enclosure" on some of the product titles we sell. This simply refers to a box ("enclosure") that includes a subwoofer already mounted in it at the factory. Some pre-loaded boxes also include built-in amplifiers.

Subwoofers Designed To Fit In Narrow Spaces

If you're looking for subwoofers that fit in tight spots, you need equipment that's specially engineered to work efficiently in a compact package. For example, there’s the Pioneer 10-inch Shallow Mount subwoofer that's sold either
with a box or
without a box.

The Pioneer 10” Shallow Mount Subwoofer and Boss 10” Bass Series Single Low Profile Subwoofer Enclosure are just several examples of slim designs that can be mounted under seats.

When space constrictions are extremely tight and under-seat mounting is the only viable option for subwoofer placement, we have slim-design equipment created to fit and produce the best sound possible from this location. The Pioneer
10” Shallow Mount Subwoofer, Audiopipe
8” Low Profile Subwoofer Enclosure, and Boss 10” Bass Series Single Low Profile Subwoofer Enclosure are just a few among many you’ll find on our website.

Bass Tubes

Another space-saving option is a bass tube. As its name suggests, these are in the shape of a tube with the subwoofer facing out one end of the tube. Because the diameter of the pipe-shaped housing isn't much larger than the subwoofer inside, tubes can fit in compact, angled spaces where square-shaped subwoofer boxes cannot. Fans of bass tubes feel they create an elongated bass effect because of natural echoing (i.e. a "Dhummm...dhummm..." sound), whereas subwoofer boxes create more of a thumping bass effect (i.e. a "dhup...dhup...dhup" sound).

Ported Subwoofer Boxes

Ported boxes are built with openings known as ports, require less power to play loud, and deliver a deeper bass tone than a sealed box. If your amp is small and/or your music features deep bass, ported subwoofer boxes are best for you. For reference, some examples we offer are the Audiopipe
12” AP-XB Series Ported Powered Subwoofer Enclosure,
Boss 12” Bass Series Dual Vented Powered Subwoofer Enclosure, and the Scosche
10” HD Series Vented Powered Subwoofer Enclosure – among others. The Dual 6.5” Dual Ported Passive Subwoofer Enclosure even includes two 3” tweeters.

Dual Bandpass Subwoofer Boxes

Bandpass boxes are subwoofers mounted in a sealed box with ported chambers in front of the driver cones. All the bandpass subwoofers we sell are equipped with two drivers, so they tend to be physically larger in size. Bandpass boxes are the best choice if you want maximum volume AND have the space to install them.

If 10-inch diameter subwoofer drivers are a good fit for your vehicle, the Pyramid® 10" 1000W Dual Bandpass Speaker System comes with neon rings around the drivers, silver polypropylene cones, and rubber insulation. Stepping up to 12-inch diameter size, choices increase. First, there's the Dual® 12-inch Dual Bandpass Subwoofer Enclosure which includes built-in crossovers, LED lights, and aluminum woofer cones (surrounds are made of foam, not rubber). The Pyle 12-inch Dual 2-Way Bandpass Box with Blue Subwoofer Rings also offers rubber insulation, high-quality polypropylene cones, and LED lighting.

Sealed Subwoofer Boxes

Subwoofers contained within sealed enclosure boxes are more compact and they make the cleanest sounding bass. Because they have no side ports for sound to escape directly out of, sealed subwoofer boxes perform their task solely by vibrating the air. However, you'll need a powerful amplifier to reach high volume levels without distortion.

If you're looking for straight, hard bass that thumps your chest, this type of subwoofer box provides the hardest punch. While ported and bandpass style boxes indicate their layout in their product titles, sealed subwoofer boxes typically do not specify the word "sealed". The Power Acoustik 12” THIN Series Low Profile Sealed 1200W Subwoofer Enclosure is an example.

Boxes By Themselves

If you're looking to build your own custom subwoofer setup, check out our Subwoofer Boxes & Enclosures sub-section. These are just the enclosure casings without any subwoofers or electronics in a wide variety of sizes, shapes, and applications to help you get started. For those products that are vehicle-specific, simply drill down on the Product Options field and select your year, make, and model vehicle. After doing so, you'll see applicable subwoofer box housings with square openings, round openings, and vents.

You'll see box housings designed for "downfire" or "front fire" sound release, and you'll see boxes sized and shaped to fit logical areas of your vehicle for subwoofer placement such as underneath seats or behind them for two-seaters and
pickup trucks.

Individual Subwoofers

If you're looking to purchase subwoofers as separate components, either to populate an empty enclosure or to replace/upgrade an existing driver, there are lots of choices in our
Component Subwoofers sub-section. In the left-hand column, checkboxes allow you to narrow your search by speaker diameter, shape (round or square), mounting depth, wattage, and other factors.

We also offer individual subwoofer drivers by themselves.

Subwoofers added to an already-outstanding car audio system will put you and your favorite tunes above anything that a factory system can offer. It's not just about hip-hop! Everything from classical to classic rock sounds better when the bass is boosted. Many of these products can be installed by you the vehicle owner; feel free to contact our audio experts at any time for product and installation suggestions and advice.

Timothy Zahl is a technical writer and product consultant at CARiD with over a decade of experience in the automotive industry. From drag racing and drifting to rallying and off-roading; Timothy is a fan of performance cars and anything that runs fast and loud. His numerous automotive articles and technical write-ups are available at CARiD knowledge base. Follow Timothy Zahl on G+, Facebook, Twitter to be up to date with his latest guides and articles.

All manufacturer names, symbols, and descriptions, used in our images and text are used solely for identification purposes only. It is neither inferred nor implied that any item sold by CARiD.com is a product authorized by or in any way connected with any vehicle manufacturers displayed on this page.